On August 21st, the Alberta Court of Appeal issued a split judgement in which the majority held that the police violated an accused person’s Charter rights by using a digital recording ammeter to gather information in support of a grow-op investigation.
An digital recording ammeter (or “DRA”) is a device that is installed on a power line to measure electrical consumption. In this case, the police asked an electrical service provider to install one to measure electrical consumption at a residence they suspected of housing a grow-op. The service provider agreed, and later produced a graphical representation of showing power consumption over five days. The graph showed a pattern of 18-hour cycles of high consumption, which is consistent with the presence of a marijuana grow-op. Partly on the strength of this evidence, the police obtained a warrant that led them to lay charges.
Whether the police violated the accused person’s reasonable expectation of privacy by conducting a warantless “DRA search” was the key issue in the case. It turned on (1) the quality of the electricity consumption information (and whether it went to the accused person’s “biographical core of personal information”) and (2) the effect of a regulatory provision promulgated under the Alberta Electrical Utilities Act that expressly permits Alberta service providers to disclose customer information to the police without consent unless contrary to their express wishes. This statutory permission, in the circumstances, was also backed by a contractual provision that warned the accused person that his information could be provided to law enforcement “for drug investigations.”
The majority held that the police violated the accused person’s reasonable expectation of privacy. It distinguished the Supreme Court of Canada decisions in both Plant (no expectation of privacy in electrical billing records) and Tessling (no expectation of privacy in heat patterns emanating from a residence) based on the quality of the information. It explained:
The DRA technology at issue in this case is not only different from the FLIR technology considered in Tessling, it is also more intrusive and more revealing. Here, the expert evidence confirmed that a DRA records the flow of electricity to a residence over a period of time. In doing so, it measures the amount of electricity being used at a given point, based on one amp increments. While the DRA does not indicate the source of electrical consumption within the residence, it produces information as to the amount of electricity being used in a home and when it is being used, all over a significant period of time. A pattern of excessive electrical use over a 12-hour or 18-hour cycle indicates to the police that a marihuana grow operation is likely being undertaken at the subject property, as marihuana is typically grown indoors using 12 or 18‑hour light cycles.
Notwithstanding the evidence of the police expert, Sgt. Morrison, DRA information must, as a matter of common sense, also disclose biographical or private information; for example, the approximate number of occupants, when they are present in the home, and when they are awake or asleep. This applies to all homes, regardless as to whether they are being used for marihuana grow operations: Patrick at para. 32. I note that in R. v. Tessling 2003 CanLII 8861 (ON C.A.), (2003), 63 O.R. (3d) 1 at para. 69, 168 O.A.C. 124 (C.A.), Abella J.A., as she then was, observed that many innocent, internal activities in the home, such as taking a bath or using lights at unusual hours, are intensely personal. Likewise in R. v. Plant, 1993 CanLII 70 (S.C.C.),  3 S.C.R. 281, 84 C.C.C. (3d) 203, McLachlin J., as she then was, albeit in dissent, observed (at 302-03) that mere billing records can disclose “important personal information”, including; “…what sort of activities were probably taking place there. The records tell a story about what is happening inside a private dwelling, the most private of places.”
On the effect of the statutory permission, the majority construed the regulation strictly, and only to permit the disclosure of recorded information about electrical consumption:
In my opinion, the Regulations must be strictly construed, and not interpreted to imply the homeowner’s consent in allowing the utility to gather, at the behest of the state, information that is not useful to his or her relationship with the utility. The Regulations cannot mean that the utility can be used, without judicial authorization, as an investigative arm of the police to gather evidence about what is happening inside the home, unless the consumer has forbidden it. Trespassing on a homeowner’s property is conduct the police themselves are not permitted to engage in (see Kokesch, Evans), and I do not understand that the Regulations were intended, nor constitutionally able, to empower police agents to do what they themselves can not legally do. In my opinion, the Regulations do no more than permit the utility to share pre-existing customer information with the police unless the customer has objected.
O’Brien J.A. issued a very thorough dissent, finding that there was no reasonable expectation of privacy the DRA record disclosed to the police, a finding he noted is the same as reached by the Saskatchewan Court of Appeal in R. v. Cheung. O’Brien J.A. reasoned that Plant and Tessling were not distinguishable and supported a finding that the DRA graph the service provider gave to the police did not reveal any part the accused person’s “biographical core of personal information.” He also reasoned that the Electrical Utilities Act regulation and the related service contract clearly permitted disclosure in the circumstances and therefore weighed heavily against an expectation of privacy.
Note that O’Brien J.A. also made two alternative findings. He held that the search was also reasonable because it was authorized by statute and, in the further alternative, by common law police powers.